Blanket lockup assembly



L. s. TYMA, JR., ETAL 3,127,834

BLANKET LOCKUP ASSEMBLY 2 Sheets-Sheet 1 4 0 MM /W 50 6 Z W April 7,1964 Filed 001;. 4, 1960 A ril 7, 1964 L. s. TYMA, JR., ETAL I 3,127,334

BLANKET LOCKUP ASSEMBLY Filed Oct. 4, 1960 2 Sheets-Sheet 2 24 3/3INVENT0R5.

100/5 .5 Zia/e, Jr: 6/! Z Pmaoy 1f f/or/reys.

A resilient outer layer. I must be properly tensioned, smooth, andperiodically re- United States Patent F 3,127,334 BLANKET LUCKUPASSEMBLY Louis S. Tyma, 3n, Hinsdale, and Glenn R. Peabody,

Villa Park, lil, assigncrs to Miehle-Goss-Dexter, Incorporated,(Ihicago, 111., a corporation of Delaware Filed Get. 4, 19%, Ser. No.6tl,4ll7 6 (Ilaims. (Cl. 161-4151) This invention relates to olfsetprinting presses and concerns more particularly a blanket cylinder forsuch presses.

The blanket cylinder for an offset press usually includes a solidcylindrical base having a resilient, flexible blanket tensioned aboutits periphery. This gives the cylinder a To operate efiiciently, theblanket placed, and hence the art has given a great deal of attention tothe securing or lockup of blanket members onto their cylinders.

It is the primary aim of the present invention to provide an improvedflexible blanket lockup arrangement that effectively positions and locksa blanket on a cylinder while being very easy to use and exceptionallyeconomical to manufacture.

In more detail, the improved blanket lockup arrangement of the inventionis particularly efiective since the blanket is tensioned by solidlysupporting both axially alined blanket edges and drawing them down withuniform force into a narrow slot. Thus, the blanket is uniformlytensioned and only the narrow slot interrupts the continuity of theblanket cylinder surface.

It is also an object to provide a lockup arrangement as described abovewhose economy results both from the simple shape of the requiredcylinder slot as well as the easily formed character of the additionalparts making up the assembly.

Moreover, it is a further object to provide a blanket lockup arrangementof the above type which is simple to manipulate when changing blanketsand which facilitates alinement of a blanket as it is positioned on acylinder.

Other objects and advantages of the invention will become apparent uponreading the following detailed description and upon reference to thedrawings in which:

FIGURE 1 is a fragmentary section, with portions broken away, of ablanket cylinder embodying the present invention;

FIG. 2 is an end section taken approximately along the line 22 of PEG. 1and showing one step in installing a blanket on the cylinder;

FIG. 3 is a fragmentary view similar to FIG. 2 showing a succeeding stepin the procedure of mounting a blanket on a cylinder;

FIG. 4 is a fragmentary view similar to FIG. 3 showing the finalposition of the parts; and

FIG. 5 is a fragmentary elevation of a modified arrangement foranchoring the edges of the blanket shown in the other figures.

While the invention will be described in connection with a preferredembodiment, it will be understood that we do not intend to limit theinvention to that embodiment. On the contrary, we intend to cover allalternatives, modifications and equivalents as may be included withinthe spirit and scope of the invention as defined by the appended claims.

Turning first to FIG. 1 there is shown a blanket cylin- "ice derassembly 10 embodying the blanket lockup arrangement of the presentinvention. The cylinder assembly 10 includes a cylindrical body 11having opposite end shaft portions 12 and 13 and a flexible resilientblanket 15 preferably formed of sheet rubber. The end shaft portions 12,13 of the cylinder are journaled in a press frame 16 by roller bearings17 of which only one is shown. The bearings 17 are carried in eccentricmounts 18 which can be rotated in the press frame 16 so as to adjust theposition of the blanket cylinder assembly.

In accordance with the invention, the blanket 15 is mounted on thecylinder body 11 by a pair of bars 21 and 22 which are secured toopposite ends of the blanket 15 and which are drawn in overlyingrelation down into a slot 23 formed in the cylinder body. The slot 23 isgenerally rectangular in cross section and presents a fairly narrowopening in the periphery of the cylinder. The slot extends axially thefull length of the cylinder body 11.

The bars 21, 22 are approximately square in cross section and aresecured to the blanket 15 by strips 24 which tightly sandwich the endsof the blanket between the strips and the respective bars 21, 22. Aseries of flat head screws 25 lock the strips and their associated barstightly together. When in assembled relation, the bars 21, 22, the endsof the blanket 15, and the strips 24 are adapted to be slidably fittedwithin the slot 23, and the combined thickness of each assembly extendssubstantially the full width of the slot.

In a slightly modified arrangement (see FIG. 5), a blanket 15acorresponding to the blanket 15 may be clamped between a bar 22a and astrip 24a by a plurality of screws 25a with the bar 22a and the strip24a having interfitting ridge and trough portions 26 and 27. The bendthus imposed in the blanket 15a securely anchors the blanket to the bar22:: and resists any tendency of the blanket to slip from between thebar 22a and the strip 24a. Alternatively, the opposed faces of the barsand strips can be knurled or otherwise roughened so as to securely gripthe blanket.

To install the blanket 15 on the cylinder body 11, the bars 21, 22 arefirst secured to the blanket ends by sandwiching the blanket edgesbetween the respective bars and the strips 24 as described above. Thefirst bar 21 is then anchored in the bottom of the slot 23 by a pair ofshoulder screws 30 which pass through lugs 31 formed at each end of thebar 21. The screws 30 are threaded firmly into tapped holes formed atthe opposite ends of the slot 23. The shoulder portions of the screws 30hold the first bar 21 with sufficient looseness to permit some lostmotion of the bar radially of the cylinder body.

With the first bar 21 anchored at the bottom of the slot 23, theoperator holds onto the free end of the blanket 15 and the cylinderassembly is slowly rotated in the direction of the arrow 32 shown inFIG. 2. Because of the solid, accurate alinement of the first bar 21both radially and axially of the cylinder body, the blanket 15 wrapsabout the cylinder body smoothly and in proper alinement as it is heldunder light tension by the operator. When this step has been completed,the parts have assumed the position shown in FIG. 2.

The second bar 22 is then disposed over the first bar 21 and a pluralityof cap screws 35 are passed through both of the bars 21, 22 intothreadable engagement with holes tapped in the bottom of the slot 23. Atthis point, both ends of the blanket are anchored within the slot 23 3and the blanket is loosely disposed about the cylinder body, theposition of the parts shown in FIG. 3.

The cap screws 35 are then tightened downwardly, driving both bars 21,22 down into the slot 23 and drawing both edges of the blanket 15 intothe slot so as to tension the blanket uniformly about the periphery ofthe cylinder body 11. Because of its lost motion anchoring, the bar 21moves down freely as the cap screws 35 are tightened so that thetensioning force/is exerted onboth edges of the blanket during thetightening step. The parts thus assume the positions shown in FIG. 4.

Those skilled in the art will appreciate that the blanket lockuparrangement illustrated and described is particularly economical tomanufacture. Contributing to this economy of construction is the factthat the slot 23 formed in the cylinder body 11 is of simple rectangularconfiguration Without requiring complicated undercutting or otherexpensive machining operations. In addition, the bars 21, 2.2 are ofsimple, square cross section and can be easily manufactured. The entireassembly requires no special hooks or clamps which would be expensive tomanufacture.

It can also be seen that it is quite simple to utilize the lockuparrangement disclosed. The operator merely has to manipulate a series ofconventional screws with ordinary tools. The anchoring arrangementprovided for the first bar 21 results in the blanket being properlyalined during the wrap-on operation. The cap screws 35, since they passthrough both of the bars 21, 22, positively aline the opposite ends ofthe blanket during the final tightening operation.

Despite its simplicity and economy, the blanket lockup arrangement ofthe present invention is quite eifective since the solid square bars 21,22 give firm support at each edge of the blanket, resulting in eventensioning as both edges of the blanket are drawn downwardly into theslot 23. It can also be seen that only a quite narrow slot is needed andhence there is little break in the outer conformation of the completeblanket cylinder assembly 10.

Although the invention has been illustrated and described in connectionwith the securing of an offset blanket onto an ofiset press blanketcylinder, it will be apparent that the invention is equally applicableto the securement of any flexible covering onto a supporting cylinder orroller. Hence, in the following claims the terms blanket and blanketcylinder have been used in their broadest sense to mean any flexiblesheet or covering and any supporting cylinder or roller, and there is nointention to limit the claimed invention to an olfset press.

We claim as our invention:

1. A flexible blanket lockup arrangement comprising, in combination, ablanket cylinder having a narrow axially extending slot in itsperiphery, a first bar secured along one edge of said blanket, saidfirst bar being slidably fitted into said slot, means anchoring saidfirst bar near the bottom of said slot with sufiicient looseness topermit some lost motion of the bar radially of the cylinder, a secondbar secured along the edge of said blanket opposite the first bar, saidsecond bar being fitted into said slot above said first bar so that thebars are radially spaced in said slot with the bottom of the second barabutting the top of the first bar, and means for drawing said second barand thus both of said bars down into said slot so as to tension theblanket uniformly about the cylinder from each of said blanket edges.

2. A flexible blanket lockup arrangement comprising, in combination, ablanket cylinder having a narrow axially extending slot in itsperiphery, a first bar secured along one edge of said blanket by anoverlying strip tightly sandwiching the blanket between the bar and saidstrip, said first bar being slidably fitted into said slot, meansanchoring said first bar at the bottom of said slot with sufficientlooseness to permit some lost motion of the bar radially of thecylinder, a second bar secured along the edge of said blanket oppositethe first bar by an overlying strip tightly sandwiching the blanketbetween the bar and the strip, said second bar being fitted into saidslot above said first bar so that the bars are radially spaced in saidslot with the bottom of the second bar abutting the top of the first barand so as to loosely dispose the blanket about said cylinder, and meansfor drawing said second bar and thus both of said bars evenly down intosaid slot so as to tension the blanket about the cylinder from each ofsaid blanket edges.

3. A flexible blanket lockup arrangement comprising, in combination, ablanket cylinder having a narrow axially extending slot in itsperiphery, said slot being rectangular in cross section and uniform indepth, a first bar of approximately square cross section secured alongone edge of said blanket, said first bar being slidably fitted into saidslot, means anchoring said first bar parallel to the bottom of said slotwith sufiicient looseness to permit some lost motion of the bar radiallyof the cylinder, a second bar of approximately square cross sectionsecured along the edge of said blanket opposite the first bar, saidsecond bar being fitted into said slot above said first bar so that thebars are radially spaced in said slot with the bottom of the second barabutting the top of the first bar and so as to loosely dispose theblanket about said cylinder, and means for drawing said second bar downinto said slot so as to urge both bars equally into the slot and thustension the blanket about the cylinder from each of said blanket edges.

,-4. A flexible blanket lockup arrangement comprising, in combination, ablanket cylinder having a narrow axially extending slot of generallyrectangular cross section in its periphery, a first bar secured alongone edge of said blanket, said first bar being slidably fitted into saidslot and extending substantially the full width of the slot, screwsanchoring said first bar to the bottom of said slot with sufficientlooseness to permit some lost motion of the first bar radially of thecylinder, a second bar secured along the edge of said blanket oppositethe first bar, said second bar being fitted into said slot above and incontact with said first bar so that the bars are radially spaced in saidslot with the bottom of the second bar abutting the top of the first barand so as to loosely dispose the blanket about the cylinder, said secondbar extending substantially the full width of the slot, and a pluralityof screws passing through both of said bars into threadable engagementwith said cylinder for drawing said second bar and thus both of saidbars down into said slot so as to tension the blanket about thecylinder.

5. A flexible blanket lockup arrangement comprising, in combination, ablanket cylinder having a narrow axially extending slot of generallyrectangular cross section in its periphery, a first bar of approximatelysquare crosssection secured along one edge of said blanket by anoverlying strip tightly sandwiching the blanket between the bar and saidstrip, said first bar being slidably fitted into said slot and extendingsubstantially the full width. of the slot, shoulder screws anchoringsaid first bar at the bottom of said slot with sufficient looseness topermit some lost motion of the first bar radially of the cylinder, asecond bar of approximately square cross section secured along the edgeof said blanket opposite the first bar by an overlying strip tighhysandwiching the blanket between the bar and said strip, said second barbeing fitted into said slot above said first bar so as to looselydispose the blanket about the cylinder, said second bar extendingsubstantially the full width of the slot, and a plurality of screwspassing through each of said bars into threadable engagement with saidcylinder for drawing said bars down into said slot so as to tension theblanket about the cylinder.

6. A flexible blanket lockup arrangement comprising, in combination, ablanket cylinder having a narrow axially extending slot in itsperiphery, a first bar secured along one edge of said blanket by anoverlying strip tightly sandwiching the blanket between the bar and saidstrip, said first bar being slidably fitted into said slot, meansanchoring said first bar at the bottom of said slot with sufficientlooseness to permit some lost motion of the bar radially of thecylinder, a second bar secured along the edge of said blanket oppositethe first bar by an overlying strip tightly sandwiching the blanketbetween the bar and the strip, said second bar being fitted into saidslot above said first bar so that the bars are radially spaced in saidslot with the bottom of the second bar abutting the top of the first barand so as to loosely dispose the blanket about said cylinder, and meansfor drawing said second bar and thus both of said bars evenly down 6into said slot so as to tension the blanket about the cylinder from eachof said blanket edges, said bars and strips having opposed irregularsurfaces between which said blanket is sandwiched so as to providesecure anchoring of said blanket to said bars.

References Cited in the file of this patent UNITED STATES PATENTS2,055,295 Kessler Sept. 22, 1936 2,121,309 Wale June 21, 1938 2,714,852Stempel Aug. 9, 1955

1. A FLEXIBLE BLANKET LOCKUP ARRANGEMENT COMPRISING. IN COMBINATION, ABLANKET CYLINDER HAVING A NARROW AXIALLY EXTENDING SLOT IN ITSPERIPHERY, A FIRST BAR SECURED ALONG ONE EDGE OF SAID BLANKET, SAIDFIRST BAR BEING SLIDABLY FITTED INTO SAID SLOT, MEANS ANCHORING SAIDFIRST BAR NEAR THE BOTTOM OF SAID SLOT WITH SUFFICIENT LOOSENESS TOPERMIT SOME LOST MOTION OF THE BAR RADIALLY OF THE CYLINDER, A SECONDBAR SECURED ALONG THE EDGE OF SAID BLANKET OPPOSITE THE FIRST BAR, SAIDSECOND BAR BEING FITTED INTO SAID SLOT ABOVE SAID FIRST BAR SO THAT THEBARS ARE RADIALLY SPACED IN SAID SLOT WITH THE BOTTOM OF THE SECOND BARABUTTING THE TOP OF THE FIRST BAR, AND MEANS FOR DRAWING SAID SECOND BARAND THUS BOTH OF SAID BARS DOWN INTO SAID SLOT SO AS TO TENSION THEBLANKET UNIFORMLY ABOUT THE CYLINDER FROM EACH OF SAID BLANKET EDGES.